title: Catalytic spectrophotometric determination of iodide in pharmaceutical preparations and edible salt.
abstract: The catalytic effect of iodide on the oxidation of four dyes: viz. variamine blue (VB), methylene blue (MB), rhodamine B (RB), and malachite green (MG) with different oxidizing agents was investigated for the kinetic spectrophotometric determination of iodide. The above catalyzed reactions were monitored spectrophotometrically by following the change in dye absorbances at 544, 558, 660, or 617 nm for the VB, RB, MB, or MG catalyzed reactions, respectively. Under optimum conditions, iodide can be determined within the concentration levels 0.064-1.27 µg mL(-1) for VB method, 3.20-9.54 µg mL(-1) for RB method, 5.00-19.00 µg mL(-1) for the MB method, and 6.4-19.0 µg mL(-1) for the MG one, with detection limit reaching 0.004 µg mL(-1) iodide. The reported methods were highly sensitive, selective, and free from most interference. Applying the proposed procedures, trace amounts of iodide in pharmaceutical and edible salt samples were successfully determined without separation or pretreatment steps.
authors.affiliation: National Organization of Drug Control and Research, Cairo, Egypt.
authors.forename: M A
authors.initials: MA
authors.lastname: El-Ries
authors.forename: Elmorsy
authors.initials: E
authors.lastname: Khaled
authors.forename: F I
authors.initials: FI
authors.lastname: Zidane
authors.forename: S A
authors.initials: SA
authors.lastname: Ibrahim
authors.forename: M S
authors.initials: MS
authors.lastname: Abd-Elmonem
mesh_terms: D002384:Catalysis; D004396:Coloring Agents / Q000737:chemistry; D005504:Food Analysis / Q000379:methods; D007454:Iodides / Q000032:analysis*; D057230:Limit of Detection; D010084:Oxidation-Reduction; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D017673:Sodium Chloride, Dietary / Q000032:analysis*; D013053:Spectrophotometry / Q000379:methods*
chemical_list: D004396:Coloring Agents; D007454:Iodides; D004364:Pharmaceutical Preparations; D017673:Sodium Chloride, Dietary